The Nebulas IO Foundation (“Nebulas”) is sponsoring the Developer Incentive Program Contest (the “Contest”), as described and subject to the Official Rules during the Contest Period (as defined in the Official Rules).
You may earn NAS coins for referring developers and participants to the Contest through the Nebulas Referral
Incentive Program (the “Referral Program”) subject to these terms and conditions (the “Referral Program Terms”). To participate, you must agree to these Referral Program Terms. All capitalized terms used in these Referral
Program Terms and not otherwise defined herein have the meanings set out in the Official Rules.

1. Eligibility: You may participate in the Referral Program only if you are 18 years or older and capable of forming a binding
contract with Nebulas, and are not barred from participating under applicable law.If you are participating in the Referral Program on behalf of a company (such as your employer) or other legal
entity, you represent and warrant that you have the authority to bind that company or other legal entity
to these Referral Program Terms. In that case, “you” and “your” will refer to that company or other legal entity. To be eligible for Referral Rewards and Monthly Incentives, you must register for the Referral Program as described
in Section 2.

2. Registration: You must register to participate in the Referral Program at the “Contest Website”during the Contest Period.

You agree to comply with all applicable national, international, state and local laws, ordinances and regulations
in connection with your participation in the Referral Program. Nothing herein shall constitute an employment, joint venture, or partnership relationship between you and Nebulas.
You are not eligible for a Referral Payment or Monthly Incentive (defined below) if you refer yourself. Nebulas
reserves the right to confirm the validity of all Referrals.

3. Referral Payments:

In exchange for each Referral (as defined below), you will receive a referral payment. You will receive an initial
reward of 40 NAS (retail value of approximately $240 (US) based on NAS prices on April 25, 2018) for each
Referral. In addition, if you make a Referral and the DApp Submission submitted by the Referred Developer
is awarded a prize in the Contest, you will receive an additional payment equal to twenty percent (20%) of
the prize (collectively and together with the initial reward, the “Referral Payments”).

A “Referral” means a referral to a Referred Developer to enter the Contest made by an individual eligible to participate in
the Referral Program, who has registered for the Referral Program, and meets each of the following conditions:
(i) the Referred Developer must enter the Contest during the Contest Period; (ii) the Referred Developer
must provide the referral code associated with the referring party that was provided to the referring party
when the referring party registered to participate in the Referral Program (the “Referral Code”); (iii) the Referred Developer must submit at least one Submission in accordance with the Official Rules during
the Contest Period; (iv) the Referred Developer complies with the Official Rules; and (v) the Referred Developer
must not have previously registered with the Contest or submitted a DApp to the Contest prior to the Referral.

A “Referred Developer” means a Contest participant referred through a Referral to participate in the Contest.

Nebulas will verify the connection between the referring party and each Submission using the Referral Code.

Each month during the Contest Period, participants in the Referral Program who make the highest number of new
Referrals during that month will receive an additional referral payment (collectively, “Monthly Incentive”):

The participant who makes the highest number of new Referrals in a month during the Contest Period will receive
10,000 NAS (retail value of approximately $60,000 (US) based on NAS prices on April 25, 2018).

The participants who make the second and third highest number of Referrals in a calendar month during the Contest
Period will receive 2,500 NAS.

The participants who make the fourth, fifth, and sixth highest number of referrals in a calendar month during
the Contest Period will receive 1,000 NAS.

Monthly Incentives will be determined after the end of each month during the Contest Period. Rankings will be
determined based on the total number of Referrals each Referral Program participant makes in the applicable
month during the Contest Period. To earn a Monthly Incentive, you must make a minimum of six (6) Referrals
in the applicable month during the Contest Period. In the event of a tie, the participant who made the highest
number of Referrals first will receive the applicable Monthly Incentive.

4. Payment Terms: Nebulas will pay you the Referral Payments, and if applicable, the Monthly Incentive, within thirty (30) days of the date you earned the Referral Payments by transferring NAS to the wallet address you provided when you registered for the Referral Program. You are responsible for the payment of all taxes associated with your receipt of payments under the Referral
Program. You agree to provide Nebulas with any additional information and complete any required tax or other
forms relating to your receipt of Referral Awards.

In the event of a dispute regarding who made a Referral, the Referral will be attributed to the authorized account
holder of the email account that you provided when you registered for the Referral Program. "Authorized account
holder" means the person who is assigned to an email address by an Internet access provider, online service
provider, or other organization (e.g., business, educational institution, etc.) that is responsible for assigning
email addresses for the domain associated with the submitted email address.

5. Termination and Change: The Referral Program, and these Referral Program Terms, will terminate at the end of the Contest Period. Nebulas
may suspend or terminate the Referral Program or your ability to participate in the Referral Program at any
time for any reason. Upon termination of these Referral Program Terms, any provisions which by their nature
should survive following termination will survive, including Sections 6 - 12.

Referral Payments or Monthly Incentives earned as a result of fraudulent activities are null and void. Nebulas
reserves the right to review and investigate all referral activities, and to disqualify participants or Referrals
if we notice any activity that we believe is abusive or fraudulent. Non-fraudulent accrued Referral Payments
or Monthly Incentives are not affected by suspension or termination of the Referral Program or an individual’s right to participate.

6. Disclaimer: In no event will Nebulas be liable to you for any special, incidental, exemplary, punitive or consequential damages
(including loss of use, data, business or profits) arising out of or in connection with your participation
in the REFERRAL PROGRAM, whether such liability arises from any claim based upon contract, warranty, tort
(including negligence), strict liability or otherwise, and whether or not Nebulas HAVE been advised of the
possibility of such loss or damage.IN NO EVENT SHALL NEBULAS’ TOTAL LIABILITY TO YOU IN CONNECTION WITH THIS REFERRAL PROGRAM EXCEED THE AMOUNT OF TEN U.S. DOLLARS ($10.00).Some jurisdictions do not allow the limitation or exclusion of liability for incidental or consequential damages,
so the above limitation or exclusion may not apply to you.

7. Indemnity: You agree to indemnify, defend and hold Nebulas, its affiliates, and their respective directors, officers, employees, advertising, promotion, fulfillment or other
coordinating agencies, and any other organizations providing services to Nebulas in connection with the Referral Program, harmless,
from any and all claims, injuries, damages, expenses or losses to person or property and/or liabilities of
any nature that in any way arise from your participation in this Referral Program, any noncompliance by you
with these Referral Program Terms, or acceptance or use of a payment from Nebulas in connection with the
Referral Program.

8. Publicity: Except where prohibited, by participating in the Referral Program, you consent to the use of your name, photo
and/or likeness, biographical information, entry and statements attributed to you (if true) for advertising
and promotional purposes, including without limitation, inclusion in Nebulas’ newsletters, the Contest Website and Nebulas’ homepages, without additional compensation.

9. Governing Law and Dispute Resolution: These Referral Program Terms are governed by the laws of the British Virgin Islands without regard to its conflict
of laws provisions. Any dispute arising out of or in connection with this Agreement, including any question
regarding its existence, validity or termination, shall be referred to and finally resolved by arbitration
administered by the BVI IAC in accordance with the BVI IAC Arbitration Rules (“BVI IAC Rules”) Any arbitration will occur in Road Town, Tortola, British Virgin Islands, unless the Parties agree otherwise.
The arbitration will be conducted confidentially by a single arbitrator appointed by the CEO of the BVI IAC
in accordance with the BVI IAC Arbitration Rules, which are hereby incorporated by reference. The courts
located in the British Virgin Islands will have exclusive jurisdiction over any appeals and the enforcement
of an arbitration decision. The language of arbitration shall be English. Notwithstanding this, you agree
that Nebulas shall still be allowed to apply for injunctive remedies (or an equivalent type of urgent legal
relief) in any jurisdiction.

10. Severability: If any provision in these Referral Program Terms is held to be invalid, void, or unenforceable, such provision
(or the part of it that is making it invalid, void or unenforceable) will be struck and not affect the validity
of and enforceability of the remaining provisions.

11. Personal Information: Nebulas may collect personal data about you online, in accordance with its privacy policy and as may be more
specifically set forth in these Referral Program Terms. Please review these Official Rules and Nebulas’ privacy policy. By participating in the Referral Program, you hereby agree to Nebulas’ collection and use of your personal information and acknowledge that you have read and accepted Nebulas’ privacy policy.

12. General: Nebulas reserves the right, in its sole discretion, to cancel, modify or suspend the Referral Program in whole
or in part, at any time and at its sole discretion, without liability to you (provided, however, that validly accrued Referral Payments or Monthly Incentives will not be affected by suspension or termination of
the Referral Program). Nebulas reserves the right to disqualify any entrant or winner, as determined by Nebulas, in its sole discretion.
These Referral Program Terms constitute the entire legal agreement between you and Nebulas in relation to
your participation’s in the Referral Program, and completely replace any prior agreements between you and Nebulas in relation to
the Referral Program.

NEBULAS

DEVELOPER INCENTIVE PROGRAM CONTEST OFFICIAL RULES

Sponsored by the Nebulas IO Foundation (“Nebulas”).

To foster a sustainable and healthy ecosystem, Nebulas is committed to encouraging more developers to continue
to build high quality decentralized applications (“DApps”) on the Nebulas Mainnet. The “Nebulas Mainnet” means the Nebulas software stack made available at https://github.com/nebulasio/go-nebulas/, as updated from time to time.

NO ENTRY FEE. NO PURCHASE NECESSARY TO ENTER OR WIN. These rules apply the Developer Incentive Program Contest
(the “Contest”). The Contest begins on May 7, 2018 at 12:00 AM and ends on July 2, 2018 at 12:00AM (the “Contest Period”).

1. Eligibility: The Contest is open to individuals aged eighteen (18) or older as of the date of entry who have an active email
account, as of the beginning of the Contest Period or legal entities permitted to enter into contests like
the Contest as of the beginning of the Contest Period.Participation in the Contest constitutes your full and unconditional agreement to and acceptance of these official
rules (“Official Rules”), and you certify to Nebulas that you have the right, legal capacity and authority to agree to the Official
Rules. If you are participating in the Contest on behalf of a company (such as your employer) or other legal
entity, you represent and warrant that you have the authority to bind that company or other legal entity
to these Official Rules. In that case, “you” and “your” will refer to that company or other legal entity.

VOID WHERE PROHIBITED.

2. Entry: To enter the Contest, select the Contest link from the Contest main page on the Nebulas Website during the Contest
Period.

Fill out the registration form in its entirety, and provide the required information to register an account.
Follow the directions for submitting your DApp (each, a “Submission”). To be eligible for consideration, each Submission must:

(i) run on the Nebulas Mainnet; and

(ii) include a front-end interface.

No mechanically reproduced mail-in entries are allowed and any use of robotic, automatic, programmed or the like
entry methods will void all such entries by such methods. Each Submission may only be entered once.

3. Intellectual Property Rights: The Nebulas Mainnet is licensed to you under the terms of the GNU Lesser General Public License version 3 (“LGPL”). Nebulas supports and encourages open source software and the open source community. As a condition to entering
this Contest, you agree to abide by the terms of the LGPL, including any obligations to provide notice, attribution,
or underlying source code.

As between Nebulas and you, you own all legal right, title and interest in and to the DApps, including any Intellectual
Property Rights therein, but excluding any part of the Nebulas Mainnet embedded, contained in, or otherwise
incorporated in the DApps. "Intellectual Property Rights" means any and all rights under patent law, copyright law, trade secret law, trademark law, and any and all
other proprietary rights.

Your use of the Nebulas Mainnet does not grant you any rights to use Nebulas’ trade names, trademarks, service marks, logos, domain names, or other distinctive brand features (the “Nebulas Brand”); you agree that you will not misappropriate any element of the Nebulas Brand.

You agree that the Nebulas Mainnet may be updated or modified without prior notice to you, and that such updates
or modifications may result in incompatibility with any DApps that you have developed or used in connection
with the Nebulas Mainnet; you further agree that certain libraries, features, tools or other elements of
the Nebulas Mainnet may become unavailable to you or to users generally (permanently or temporarily), without
prior notice to you. You agree that Nebulas has no obligation to update, maintain, or provide maintenance
or other support for the Nebulas Mainnet. If Nebulas makes updates or additional tools, software, or other
resources for the Nebulas Mainnet available, each will be governed by the license terms distributed with
such resource.

4. Your Use of the Nebulas Mainnet: You agree that your use of the Nebulas Mainnet, and any DApps that you develop for use in connection with the
Nebulas Mainnet will not:

violate any applicable law, regulation or generally accepted practices or guidelines in the relevant jurisdictions
(including any laws regarding the export of data or software to and from the United States or other relevant
countries);

violate any guidelines published on Nebulas’ website relating to the Contest, the Nebulas Mainnet or development of the DApps;

adversely affect the goodwill of Nebulas;

be offensive or defamatory, or contain vulgar or profane language, as determined by Nebulas;

commit any activities which harm or attempt to harm Nebulas Protocol;

interfere with, disrupt, damage or access in an unauthorized manner the servers, networks, or other properties
or services of any third party, including but not limited to Nebulas, and third-party applications such
as cryptocurrency wallets;

infringe or misappropriate any third-party Intellectual Property Rights, or otherwise facilitate or commit
any unlawful or illegal activity; or

To the extent that your use of the Nebulas Mainnet or DApp results in collection of information or provision
of services to third-party users, you agree that you will adequately and securely protect the privacy and
legal rights of those users, including by providing and adhering to legally adequate privacy notices and
by complying with all applicable privacy and data security laws and regulations.

5. Third-Party Applications: You may use applications, tools, software, content, data or other resources developed by third parties, including
other users of the Nebulas Mainnet or third-party development tools (“Third Party Applications”) in connection with the Nebulas Mainnet. If you use Third Party Applications, regardless of whether such Third
Party Applications are hosted or distributed through the Nebulas Mainnet, you agree that Nebulas is not responsible
for Third Party Applications. You understand that all data, content or resources which you may access through
Third Party Applications are the sole responsibility of the person from which they originated and that Nebulas
is not liable for any loss or damage that you may experience as a result of the use or access of any of those
Third Party Applications.

You understand and agree that (i) the data, content, and resources presented to you through such a Third Party
Application may be protected by Intellectual Property Rights which are owned by the providers or owners of
the Third Party Application, and (ii) your use of Third Party Applications may be subject to separate terms
between you and the relevant third party, and Nebulas is not party to such terms and conditions.

6. Prize Selection:

Submissions will be judged by a panel of 3 members of the Nebulas Technical Teamwith expertise in programming DApps (the “Technical Team”). The Technical Team will evaluate Submissions based on (i) the ease of use of the user interface, (ii) the aesthetic design of the user interface, (iii) the utility
of the DApp, and (iv) how smoothly the DApp functions without technical problems or bugs. To evaluate Submissions for weekly awards, the Technical Team will also take into account the results of a
ranking algorithm designed to measure the quality of the Submission, (the “Algorithm”). The Algorithm will use a number of criteria in calculating the ranking of a DApp (such as the importance of
an account address by evaluating the transfer record of the account address over a period of time), as the
Algorithm is further described at https://nebulas.io/incentive_spec.html.

The entrant whose Submission earns the highest overall score as determined by the Technical Team will win. The
decisions of the Technical Team will be final. If any ties must be broken to determine the winner, the Technical
Team will choose the tied submission by evaluating the usefulness of the DApp. Each Submission must be original, and of entrant's own creation. Each Submission must not have been entered
in any other competition, including other competitions conducted by Nebulas. Submissions will be automatically
disqualified if the Submission violates Sections 3 and 4 of these Official Rules.

Entry of a Submission constitutes your certification that the Submission is your own original work, does not
infringe the Intellectual Property Rights or proprietary rights of any third party, and does not include
Third Party Applications. Nothing herein shall constitute an employment, joint venture, or partnership relationship
between you and Nebulas.

Winners will be notified by email.

7. Prizes and Odds: You may receive a “New App Award” of One Hundred (100) NAS (retail value of approximately $600 (US) based on NAS prices on April 25, 2018) if the
Technical Team determines that your Submission makes a substantial contribution to the Nebulas ecosystem
based on the evaluation criteria. Nebulas will award up to Four Thousand Three Hundred Sixty (4,360) New
App Awards. New App Awards will be evaluated and awarded on a rolling basis, in the order that each Submission
is entered.

Weekly prize winners will be selected on a weekly basis starting on each Monday and ending on each Sundayduring the Contest Period. Each week, the First Place, Second Place and Third Place winners will be selected
from the Submissions submitted prior to the end of each applicable week, excluding those Submissions that
have won the weekly First Place, Second Place or Third Place prizes previously during the Contest Period.
The prizes to be awarded from the Contest at each weekly prize selection are as follows:

(a) One (1) First Place Prize: Ten Thousand (10,000) NAS retail value of approximately $60,000 (US) (based on
NAS prices on April 25, 2018) per winner.

(b) One (1) Second Place Prize: Five Thousand (5,000) NAS retail value of approximately $30,000 (US) (based on
NAS prices on April 25, 2018) per winner.

(c) One (1) Third Place Prize: Three Thousand (3,000) NAS retail value of approximately $18,000 (US) (based on
NAS prices on April 25, 2018) per winner.

A Monthly Championship prize will be determined on a monthly basis. Each month during the Contest Period (May 7 to June 6, 2018; June 7 to July 2, 2018) the winners will be selected from the twelve (12) First Place, Second Place and Third Place weekly prize winners
in that month. The prizes to be awarded from the Contest at each monthly prize selection are as follows:

One (1) Monthly Championship Prize will be awarded from the Contest at each monthly prize selection as follows:
Twenty Thousand (20,000) NAS retail value of approximately $120,000 (US) (based on NAS prices on April 25,
2018) per winner.

The odds of winning a prize depend on the total number of eligible entries received. No cash or other substitution
of prizes is permitted, except at the sole option of Nebulas for a prize of equal or greater value. Nebulas
will not replace any lost or stolen prizes. Winners are solely responsible for any and all federal, state,
provincial and local taxes, if any, that apply to prizes.

Total value of all prizes to be awarded: 460,000 NAS (retail value of approximately $2,760,000 (US) based on
NAS prices on April 25, 2018)

Allow six (6) to eight (8) weeks for delivery of prizes.

8. Notification of Winners: Winners will be notified by email within ten (10) business days of the prize selection, and may be required to sign and return an affidavit of eligibility and
publicity/liability release within seven (7) days of notification. If a selected winner cannot be contacted, is ineligible, fails to claim a prize and/or
where applicable an affidavit of eligibility and publicity/liability release is not timely received, is incomplete
or modified, the prize may be forfeited and an alternate winner will be selected from remaining valid, eligible
entries timely submitted. In the event of a dispute regarding who submitted an entry, the entry will be deemed
submitted by the authorized account holder of the email account specified in the entry. "Authorized account holder" is defined as the natural person who is assigned to an email address by an Internet access provider, online
service provider, or other organization (e.g., business, educational institution, etc.) that is responsible
for assigning email addresses for the domain associated with the submitted email address. No automatically
generated entries will be accepted.

9. Disclaimer: Nebulas is not responsible for (i) late, lost, delayed, damaged, postage-due, incomplete, illegible, misdirected
or undeliverable entries, responses, or other correspondence, whether by email or postal mail or otherwise;
(ii) theft, destruction, unauthorized access to or alterations of entry materials; or (iii) phone, electrical,
network, computer, hardware, software program or transmission malfunctions, failures or difficulties. Contest
prizes will be issued in the form of NAS coins. Nebulas is not responsible for any changes in NAS price.

You acknowledge that the Nebulas Protocol facilitates a decentralized, peer-to-peer network supported by independent
third-parties, and that the network is not controlled or operated by Nebulas. You agree that your use of
the Nebulas Mainnet, including the release of any DApps through the Nebulas Mainnet, may be public and recorded
on the distributed ledger of the Nebulas Mainnet. Information about your use of the Nebulas Mainnet or any
data or information that you provide in connection with your use of the Nebulas Mainnet may be shared with
any and all other users of the Nebulas Mainnet. You agree that you are solely responsible for (and that Nebulas
has no responsibility to you or to any third party for) any data, content, or resources that you create,
transmit or display through the Nebulas Mainnet, and for the consequences of your actions (including any
loss or damage which Nebulas may suffer) by doing so.

You agree that you are responsible for the security of the server, personal computer, or other device owned by
you or any third party (“User Device”) that you use in connection with the Nebulas Mainnet. You agree that Nebulas will have no responsibility to
you or any third party in the event a User Device experiences a technical failure or is otherwise compromised,
including for any loss of Nebulas or other tokens, or access to any Nebulas contracts or DApps.

In no event will Nebulas be liable to you for any special, incidental, exemplary, punitive or consequential damages
(including loss of use, data, business or profits) arising out of or in connection with your participation
in the Contest OR YOUR USE OF THE NEBULAS MAINNET, whether such liability arises from any claim based upon
contract, warranty, tort (including negligence), strict liability or otherwise, and whether or not Nebulas
HAVE been advised of the possibility of such loss or damage.IN NO EVENT SHALL NEBULAS’ TOTAL LIABILITY TO YOU IN CONNECTION WITH THE CONTEST FOR ALL DAMAGES EXCEED THE AMOUNT OF TEN U.S. DOLLARS ($10.00).Some jurisdictions do not allow the limitation or exclusion of liability for incidental or consequential damages,
so the above limitation or exclusion may not apply to you.

10. Indemnity: You agree to indemnify, defend and hold Nebulas, its affiliates, and their respective directors, officers, employees, advertising, promotion, fulfillment or other
coordinating agencies, and any other organizations providing services to Nebulas in connection with the Contest, harmless, from any
and all claims, injuries, damages, expenses or losses to person or property and/or liabilities of any nature
that in any way arise from your participation in this Contest, or any DApps you develop or submit, your use
of the Nebulas Mainnet, any noncompliance by you with these Official Rules, or acceptance or use of a prize
or parts thereof.

11. Publicity Rights: Except where prohibited, by participating in the Contest, you consent to the use of your name, photo and/or likeness,
biographical information, entry and statements attributed to you (if true) for advertising and promotional
purposes, including without limitation, inclusion in Nebulas’ newsletters, the Contest website and Nebulas’ homepages at https://nebulas.io/, without additional compensation.

12. Governing Law and Dispute Resolution: These Official Rules are governed by the laws of the British Virgin Islands without regard to its conflict of
laws provisions. Any dispute arising out of or in connection with this Agreement, including any question
regarding its existence, validity or termination, shall be referred to and finally resolved by arbitration
administered by the BVI IAC in accordance with the BVI IAC Arbitration Rules (“BVI IAC Rules”) Any arbitration will occur in Road Town, Tortola, British Virgin Islands, unless the Parties agree otherwise.
The arbitration will be conducted confidentially by a single arbitrator appointed by the CEO of the BVI IAC
in accordance with the BVI IAC Arbitration Rules, which are hereby incorporated by reference. The courts
located in the British Virgin Islands will have exclusive jurisdiction over any appeals and the enforcement
of an arbitration decision. The language of arbitration shall be English. Notwithstanding this, you agree
that Nebulas shall still be allowed to apply for injunctive remedies (or an equivalent type of urgent legal
relief) in any jurisdiction.

13. Personal Information: Nebulas may collect personal data about you online, in accordance with its privacy policy and as may be more
specifically set forth in these Official Rules. Please review these Official Rules and Nebulas’ privacy policy. By participating in the Contest, you hereby agree to Nebulas’ collection and use of your personal information and acknowledge that you have read and accepted Nebulas’ privacy policy.

14. General: Nebulas reserves the right, in its sole discretion, to cancel, modify or suspend the Contest in whole or in part,
in the event of fraud, technical or other difficulties or if the integrity of the Contest is compromised,
without liability to you. If any provision in these Official Rules is held to be invalid, void, or unenforceable, such provision (or the
part of it that is making it invalid, void or unenforceable) will be struck and not affect the validity of
and enforceability of the remaining provisions. Nebulas reserves the right to disqualify any entrant or winner, as determined by Nebulas, in its sole discretion.
The Contest, and these Official Rules, will terminate at the end of the Contest Period. Sections 3 (Intellectual
Property Rights), 4 (Your Use of the Nebulas Mainnet), 5 (Third-Party Applications), 9 (Disclaimer), 10 (Indemnity),
11 (Publicity Rights), 12 (Governing Law and Dispute Resolution), 14 (General), and any other provisions
which by their nature should survive following the end of the Contest Period will survive the expiration
or termination of the Contest. You must comply with all applicable export laws and regulations that apply
to the Nebulas Mainnet. These Official Rules constitute the whole legal agreement between you and Nebulas
(excluding any services which Nebulas may provide to you under a separate written agreement) and govern your
participation in the Contest, and completely replace any prior agreements between you and Nebulas in relation
to the Contest.

15. Winner’s List, Official Rules: For a list of prize winners or a copy of these Official Rules, send an email message to contac[email protected] with “Winner’s list” as the email subject and contest name specified in the body of the email.